IMPROVEMENT IN METAL WHEELS.

In the Inventions Exhibitions may be seen a good form of metal wheel,

the invention of Mr. H.J. Barrett, of Hull, Eng., and which we

illustrate.

[Illustration: FIG. 1. FIG. 2. FIG. 3.]

Fig. 1 is a perspective view of the wheel, Fig. 2 a transverse section,

and Fig. 3 a longitudinal section of the boss. These wheels are made in

two classes, A and B. Our engraving illustrates a wheel of the former

class, these wheels being designed for use on rough and uneven roads,

and when very great jolting strains may be met with, being stronger than

those of class B design. The wheels are made with mild steel spokes,

which are secured by metal straps in the recesses cut in the annular

flanges on the boss, and by a taper bolt or rivet through the tire and

rim. These spokes can be easily taken out and renewed when necessary by

any unskilled person in a few minutes. The spokes being twisted midway

of their length give greater strength to the wheel and power to resist

side strains in pulling out of deep ruts or holes, without increasing

the weight. The bosses and straps are made of malleable iron, in which

the metal bushes are secured by means of a key with a washer screwed up

on the front end. They are also fitted with steel oil caps to the end of

the bushes, which are provided with a small set screw, so that the cap

need not be taken off when it is necessary to lubricate the wheel, as by

simply taking out the set screw oil may be poured through the hole into

the cap. The set screw also forms a fulcrum for a key, so that the cap

can be taken off or put on when required, as well as a means of

preventing the cap being lost by shaking loose on rough roads. In all

hot and dry climates, the continued shrinking of wood wheels and

loosening of the tires is a constant source of expense and

inconvenience. This wheel having a tire and rim entirely of metal does

away with the difficulty, as the expansion and contraction are equal,

consequently the tires need only be removed when worn out, and others

can be supplied, drilled complete, ready for putting on, which can be

done by any unskilled person. The wheels of class B design are the same

in principle of construction as those of class A, but they have cast

metal bosses or naves, without loose bushes, and are suitable for

general work and ordinary roads where the strains are not so severe. The

bosses or naves are readily removed in case of breakage, and they can be

fitted with steel oil caps for lubricating.--_Iron_.

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Scientific American Supplement, No. 514, November 7, 1885 · 第 46 / 68 题